Walk power mower with biased handle

ABSTRACT

A walk power mower having a cutting deck supported upon the ground by front and rear wheels. The mower includes a biased handle that permits the handle to be pivotally displaced downwardly, against an upward bias force, during operation. The bias force may be provided by a resilient member that compresses as the handle is displaced downwardly. The compression of the resilient member allows downward movement of the handle without initially producing corresponding upward movement of the front wheels of the mower during rearward pulling of the handle.

This application is a continuation-in-part of U.S. patent applicationSer. No. 15/195,648, filed Jun. 28, 2016, the content of which isincorporated herein by reference in its entirety.

TECHNICAL FIELD

Embodiments of the present disclosure relate to a walk power mower forcutting grass and, more particularly, to a biased operator handle foruse with such a mower.

BACKGROUND

Walk power mowers are well known for cutting grass. For example, suchmowers are commonly used by property owners, such as homeowners, to cuttheir lawns. Such mowers have a cutting deck that houses a rotary grasscutting blade. The deck is supported by a plurality of wheels forrolling over the ground. A handle extends upwardly and rearwardly fromthe deck. A user who walks on the ground behind the deck grips a handlegrip of the handle to manipulate and guide the mower during a grassmowing operation.

It can be difficult or is undesirable for some users to manually push awalk power mower over the ground in order to cut one's lawn. It istiring to do so, particularly when the area being mowed is either large,hilly, or both. Thus, many mowers have traction drive systems thatutilize part of the power generated by the prime mover carried on themower to drive at least one pair of the mower's wheels, either the frontwheels or the rear wheels, in a forward direction. Such a self-propelledmower relieves the user of the necessity of having to bodily push themower over the ground. This greatly eases the physical effort requiredfrom the user in mowing one's lawn. The user now primarily guides orsteers the mower during the powered forward motion provided by thetraction drive system and the prime mover.

There are times when mowing one's lawn when the user needs to pull themower in reverse at least over short distances. For example, when a usercuts grass under the branches of a bush, the user will ordinarily drivethe mower forwardly so that the cutting blade reaches under the branchessufficiently to cut whatever patch of grass lies beneath the branches.However, once this patch of grass is cut, the user must pull back on thehandle to pull the mower out from under the branches of the bush. Whilethe traction drive system is designed with a one way clutch to allow thedrive wheels to free-wheel during reverse motion so that the user is notpulling back against the resistance provided by the gearing in thetraction drive system, the drive wheels of the mower are typicallyunpowered during this reverse motion.

As a result, many users end up having to manhandle or wrestle the mowerback in this reverse motion scenario. This requires the user to expendphysical energy and for some users accomplishing manual reverse motionof the mower may be difficult or impossible in some situations. Thisdifficulty is exacerbated for those users in which trimming operationsrequiring reverse motions of the mower are numerous or are required ondifficult terrain. For example, in trimming beneath a bush, pulling backon the mower is even more difficult if the user has to pull the mowerback up a slope to get it out from under the branches of the bush.

Another problem sometimes present during reverse mower movement isunintentional lifting of the mower's front wheels. That is, when apulling force is applied at the offset mower handle, a moment isproduced that causes the mower to rotate about a line of contact betweenthe ground and the rear wheels. As one can appreciate, this rotation maycause the mower's front wheels to lift. While such lifting of the frontwheels may be beneficial for various mower operations (e.g., turning),maintaining front wheel engagement with the ground during reverse may beadvantageous (e.g., to maintain quality of cut).

SUMMARY

One aspect of the present disclosure relates to a walk power mowerincluding: a grass cutting deck surrounding a grass cutting member,wherein the cutting deck is adapted to travel over the ground in both aforward direction and a reverse direction; and a handle comprising anupwardly and rearwardly extending handle member. The handle memberincludes an upper end comprising a grip area, and a lower end pivotallyattached to the cutting deck such that the handle member pivots about atransverse pivot axis within an operating range of pivotal motiondefined by: an upper stop corresponding to the handle being in a firstoperating orientation; and a lower stop corresponding to the handlebeing in a second operating orientation, the operating range of pivotalmotion being at least about 5 degrees. A resilient member is operativelypositioned between the lower stop and the handle member, wherein theresilient member is adapted to bias the handle member to a location ator near the upper stop.

In another aspect, the present disclosure relates to a walk power mowercomprising: a grass cutting deck supported upon the ground by a frontwheel and a rear wheel, the cutting deck surrounding a grass cuttingmember, wherein the cutting deck is adapted to traverse the ground inboth a forward direction and a reverse direction; at least onetransmission adapted to selectively provide driving power to at leastone wheel of the front and rear wheels; and a handle comprising firstand second laterally spaced-apart and parallel handle members eachextending upwardly and rearwardly from the cutting deck. The first andsecond handle members each comprise: an upper end; and a lower endpivotally attached to the cutting deck such that the handle memberspivot about a transverse pivot axis within an operating range of pivotalmotion defined by: an upper stop corresponding to the handle being in afirst operating orientation; and a lower stop corresponding to thehandle being in a second operating orientation, the operating range ofpivotal motion being about 5-20 degrees. A control member is carried ator near the upper ends of the first and second handle members, whereinthe control member, when moved to a first engaged position, is adaptedto place the transmission into operation so that the transmissionpropels the mower in the forward direction. First and second resilientmembers are provided and positioned between the deck and the first andsecond handle members, respectively, the first and second resilientmembers adapted to bias the first and second handle members to alocation at or near the upper stop.

In still another aspect, a walk power mower is provided that includes: agrass cutting deck supported upon the ground by a pair of front wheelsand a pair of rear wheels, the cutting deck surrounding at least onegrass cutting blade; and a variable speed traction drive system carriedon the cutting deck and adapted to selectively provide driving power toat least one wheel of the front and rear pairs of wheels to propel themower over the ground in both a forward direction and a reversedirection. A handle is also provided and includes first and secondlaterally spaced-apart and parallel handle members extending upwardlyand rearwardly from the cutting deck, wherein the first and secondhandle members each comprise: an upper end; and a lower end pivotallyattached to a rear portion of the cutting deck such that the handlemembers pivot about a transverse pivot axis within an operating range ofpivotal motion defined by an upper stop and a lower stop. The mower alsoincludes a control system carried at or near the upper ends of the firstand second handle members, the control system operable to engage thetraction drive system to selectively propel the cutting deck in both theforward direction and the reverse direction. First and second resilientmembers are provided and positioned between the deck and the first andsecond handle members, respectively. The first and second resilientmembers are adapted to resiliently deform when the handle members pivot,about the transverse pivot axis, from a position at or near the upperstop toward a position at or near the lower stop.

Yet another aspect of this disclosure relates to a walk power mowerwhich comprises a deck supported by a pair of front wheels and a pair ofrear wheels. The deck has at least one grass cutting blade that rotatesin a substantially horizontal plane about a substantially vertical axisto cut grass. The deck also has an upwardly and rearwardly extendinghandle that is gripped by a user who walks on the ground behind the deckto guide and manipulate the deck during motion of the deck over theground. A prime mover is carried by the deck, the prime mover beingoperably coupled to the blade for effecting powered rotation of theblade. A variable speed traction drive system is carried on the deck,the prime mover being operably coupled to the traction drive system foreffecting powered rotation of the front wheels and the rear wheels. Thetraction drive system comprises a rear transmission having a rear axlethat is operatively connected to the rear wheels for powering the rearwheels to provide self-propelled motion of the deck in a first directionof motion over the ground, a front transmission having a front axle thatis operatively connected to the front wheels for powering the frontwheels to provide self-propelled motion of the deck in a seconddirection of motion over the ground that is opposite to the firstdirection of motion, and a control system carried on the handle that isselectively operable by a user for placing only one transmission at atime into operation so that the rear transmission is active to propelthe deck in the first direction while the front transmission is inactiveor the front transmission is active to propel the deck in the seconddirection while the rear transmission is inactive.

Yet another aspect of this disclosure relates to a walk power mowerwhich comprises a traction drive system on a grass cutting deck having apair of front wheels and a pair of rear wheels. A pair of transmissionspower at least one pair of wheels on the deck. A first one of thetransmissions provides forward motion of the mower when it is active anda second one of the transmissions provides rearward motion of the mowerwhen it is active. A slidable handle grip is provided on a handleextending upwardly and rearwardly from the cutting deck. The handle griphas a cross bar long enough to be gripped by both hands of the user. Thehandle grip activates the first one of the transmissions when it is sliddownwardly on a handle out of a neutral position thereof as a user walksforwardly holding the cross bar of the handle grip. The handle gripactivates the second one of the transmissions when it is slid upwardlyon the handle out of the neutral position as a user walks rearwardlyholding the cross bar of the handle grip.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of this disclosure will be described more fully in thefollowing Detailed Description, when taken in conjunction with thefollowing drawings, in which like reference numerals refer to likeelements throughout.

FIG. 1 is a perspective view of one embodiment of a walk power moweraccording to this disclosure;

FIG. 2 is an enlarged perspective view of a portion of the handle of themower of FIG. 1, particularly illustrating the return to neutral systemthat causes the slidable handle grip of the handle to return to aneutral position in which the traction drive system is disengaged oncethe user releases the handle grip;

FIG. 3 is a perspective view of the underside of the cutting deck of themower of FIG. 1, particularly illustrating the dual transmissiontraction drive system;

FIG. 4 is a perspective view of a portion of a second embodiment of awalk power mower according to this disclosure;

FIG. 5 is an enlarged perspective view of a portion of the handle of themower of FIG. 4, particularly illustrating a second embodiment of thereturn to neutral system that causes the slidable handle grip of thehandle to return to a neutral position in which the traction drivesystem is disengaged once the user releases the handle grip;

FIGS. 6A-6B illustrate a mower in accordance with another embodiment ofthis disclosure, the mower incorporating a biased or “floating” handle,wherein: FIG. 6A is a rear perspective view; and FIG. 6B is a frontperspective view;

FIG. 7 is an enlarged view of a portion of the mower of FIGS. 6A-6B;

FIG. 8 is an exploded perspective view of a portion of the mower ofFIGS. 6A-6B;

FIG. 9 is a perspective view of a resilient member for use with themower of FIGS. 6A-6B; and

FIG. 10 is a side elevation view of the mower of FIGS. 6A-6B.

The figures are rendered primarily for clarity and, as a result, are notnecessarily drawn to scale. Moreover, various structure/components,including but not limited to fasteners, electrical components (wiring,cables, etc.), and the like, may be shown diagrammatically or removedfrom some or all of the views to better illustrate aspects of thedepicted embodiments, or where inclusion of such structure/components isnot necessary to an understanding of the various exemplary embodimentsdescribed herein. The lack of illustration/description of suchstructure/components in a particular figure is, however, not to beinterpreted as limiting the scope of the various embodiments in any way.Still further, “Figure x” and “FIG. x” may be used interchangeablyherein to refer to the figure numbered “x.”

DETAILED DESCRIPTION

One embodiment of a walk power mower 2 according to this disclosure isillustrated in FIG. 1. Mower 2 comprises a cutting deck 4 that is formedwith a generally toroidal cutting chamber 6 that faces downwardly and isopen at its bottom. Deck 4 is supported for rolling over the ground by apair of front wheels 8 and a pair of rear wheels 10. A prime mover 12,such as an internal combustion engine, is carried on top of deck 4.Referring now to FIG. 3, the drive shaft 14 of the prime mover extendsvertically downwardly with its lower end extending into cutting chamber6. A horizontal cutting member or blade 16 is positioned within cuttingchamber 6 and is removably secured to the lower end of drive shaft 14 torotate in a generally horizontal cutting plane to cut grass.

Referring again to FIG. 1, mower 2 is a three-in-one mower having sidedischarge, rear bagging and mulching modes of operation. In the sidedischarge mode, a side discharge chute 18 can be mated with a sidedischarge opening to discharge grass clippings to the side of mower 2when a side discharge door 20 is opened. In the rear bagging mode, agrass clipping collection bag 22 is mated with a rear discharge openingto collect grass clippings being discharged to the rear of mower 2 whena rear discharge door 24 is opened. While FIG. 1 illustrates deck 4 asbeing both in the side discharge mode and the rear bagging mode, this isonly for the purpose of illustration as these two modes would not beused simultaneously. When side discharge chute 18 is removed and sidedischarge door 20 is closed and when bag 22 is removed and reardischarge door 24 is closed, mower 2 is placed into its mulching mode inwhich grass clippings are driven downwardly out of cutting chamber 6 todischarge the clippings beneath mower 2. However, mower 2 need not havemultiple modes of operation, but could be built as a single purpose sidedischarge, rear bagger, or mulching mower.

An upwardly and rearwardly extending handle 26 comprising a pair oflaterally spaced handle members or tubes 28 joined by a top cross member30 may be included as shown. The lower ends of handle tubes 28 areattached to the rear of deck 4. Handle 26 includes a U-shaped handlegrip 32 that has a pair of laterally spaced legs 34 connected togetherby an upper cross bar 36. Legs 34 of handle grip 32 are telescopicallyreceived on handle tubes 28 of handle 26 for sliding movement relativethereto. Thus, handle grip 32 is able to slide downwardly on handletubes 28 as a user walks forwardly while gripping cross bar 36 of handlegrip 32 with both of the user's hands.

Handle grip 32 slides downwardly by an amount that depends upon how fastthe user walks forwardly. As will be described in more detail hereafter,the extent or amount of downward travel of handle grip 32 controls atraction drive system 38 (see FIG. 3) of mower 2 to vary the forwardground speed of mower 2 to correspond to the user's walking pace. Thistype of speed controlling, slidable handle grip is used on the PersonalPace® line of walk power mowers manufactured and sold by The ToroCompany, the assignee herein. In addition, this type of slidable handlegrip is disclosed more fully in U.S. Pat. No. 6,082,083 to Stalpes etal., which patent is hereby incorporated by reference and shall bereferred to as “Stalpes” hereafter.

In Stalpes, handle grip 32 is in a neutral, i.e., a drive disengagedposition, when handle grip 32 is at the top of handle 26 with handlegrip 32 located adjacent to cross member 30 that joins handle tubes 28together. The only control motion of handle grip 32 in Stalpes is thedownward sliding motion that engages the traction drive system ofStalpes in forward and that varies the forward ground speed in concertwith the user's forward walking pace. When the user lets go of handlegrip 32 in Stalpes, handle grip 32 is spring biased to slide back uphandle 26 to return to the top thereof at which point the traction drivesystem becomes disengaged once again.

In mower 2 of this disclosure, the Stalpes handle grip 32 has beenmodified so that the neutral position of handle grip 32 is no longer atthe top of the range of motion of handle grip 32. Now, the neutralposition of handle grip 32 is displaced somewhat downwardly from crossmember 30 of handle 26. A return to neutral system 40 maintains handlegrip 32 in its now lower neutral position relative to cross member 30 ofhandle 26.

Handle grip 32 functions as it did in Stalpes when the user grips crossbar 36 of handle grip 32 and walks forwardly, i.e., handle grip 32slides downwardly in the direction of the arrow A in FIG. 1 to activatetraction drive system 38 in forward and to vary the forward ground speedin concert with the user's forward walking pace. Now, however, if theuser grips cross bar 36 of handle grip 32 and walks rearwardly, as whenpulling mower 2 back, handle grip 32 is now also able to slide upwardlyout of neutral rather than being held in neutral as in Stalpes. Thisupward sliding motion of handle grip 32 is shown by the arrow B inFIG. 1. This activates traction drive system 38 in reverse and variesthe reverse ground speed of mower 2 in concert with the user's rearwardwalking pace. In either forward or reverse powered motion of mower 2,when the user lets go of handle grip 32, return to neutral system 40causes handle grip 32 to slide back to its centered neutral positionbetween the lower and upper limits of the range of motion of handle grip32 to disengage traction drive system 38.

Referring now to FIG. 2, return to neutral system 40 comprises a rod 42having an upper end fixed by a bracket 44 to a laterally extending crossmember 46 that is also part of handle grip 32. Rod 42 has spaced upperand lower push nuts 48 _(u) and 48 _(l) fixed thereto to move with rod42. Push nuts 48 bear respectively against one end of cylindrical, upperand lower, push tubes 50 _(u) and 50 _(l) which are spaced along thelength of rod 42 and through which rod 42 slides. Each push tube 50 hasan annular thrust surface 52 that is formed as an integral part thereof.Push tubes 50 are assembled in an inverted relationship relative to eachother along the length of rod 42 such that thrust surface 52 of upperpush tube 50 _(u) is at the lowermost end of upper push tube 50 _(u)while thrust surface 52 of lower push tube 50 _(l) is at the uppermostend of lower push tube 50 _(l).

Return to neutral system 40 further includes a U-shaped clevis 54 fixedto handle 26 with the spaced, parallel side walls 56 of clevis 54forming an upper wall 56 _(u) and a lower wall 56 _(l). Upper and lowerpush tubes 50 _(u) and 50 _(l) when assembled on rod 42 are arranged topass through bores in upper and lower walls 56 _(u) and 56 _(l) ofclevis 54 with thrust surfaces 52 on upper and lower push tubes 50 _(u)and 50 _(l) being inside clevis 54 immediately adjacent to upper andlower walls 56 _(u) and 56 _(l) of clevis 54. A compression spring 58 isarranged inside clevis 54 with the ends of spring 58 bearing againstthrust surfaces 52 of upper and lower push tubes 50 _(u) and 50 _(l).When return to neutral system 40 is properly adjusted and traction drivesystem 38 is in neutral, spring 58 will force upper and lower push tubes50 _(u) and 50 _(l) apart until thrust surfaces 52 thereon abut againstthe upper and lower walls 56 _(u) and 56 _(l) of clevis 54 and theopposite ends of upper and lower push tubes 50 _(u) and 50 _(l) areimmediately adjacent to upper and lower push nuts 48 _(u) and 48 _(l).

When the user pushes down on handle grip 32 to initiate powered forwardmotion of mower 2, upper push nut 48 _(u) on rod 42 presses down on theupper end of upper push tube 50 _(u) to slide upper push tube 50 _(u)downwardly relative to clevis 54. Note that lower push tube 50 _(l)remains stationary with rod 42 simply sliding through lower push tube 50_(l) since the lower push nut 48 _(l) moves away from the lowermost endof lower push tube 50 _(l) and lower push tube 50 _(l) remains withinclevis 54 since thrust surface 52 on lower push tube 50 _(l) is held inplace by its engagement with lower wall 56 _(l) of clevis 54. Thedownward motion of upper push tube 50 _(u) compresses spring 58downwardly. Thus, when the user eventually releases handle grip 32, thecompressed spring 58 pushes back upwardly on upper push tube 50 _(u) tocause the uppermost end of upper push tube 50 _(u) to push the upperpush nut 48 _(u) back upwardly, thereby returning handle grip 32 to itscentered neutral position.

Return to neutral system 40 works the same way but in an oppositefashion when handle grip 32 is pulled upwardly in the direction of thearrow B to initiate reverse powered motion of mower 2. This time it islower push tube 50 _(l) that is pushed upwardly by lower push nut 48_(l) with upper push tube 50 _(u) remaining stationary. Thus, spring 58is compressed upwardly. When handle grip 32 is eventually released, thelowermost end of lower push tube 50 _(l) pushes downwardly on lower pushnut 48 _(l) as the upward compression of spring 58 is released to slidehandle grip 32 back downwardly to return handle grip 32 to its centeredneutral position.

Referring now to FIG. 3, traction drive system 38 comprises a first reartransmission 60 _(r) which powers rear wheels 10 of mower 2 and a secondfront transmission 60 _(f) which powers front wheels 8 of mower 2.Transmissions 60 preferably comprise, but are not limited to, mechanicalgear drive transmissions that use various speed reduction stages toreduce the relatively high rotational speed of drive shaft 14 of primemover 12 to a lower speed suitable for self-propelling mower 2 at groundspeeds that match the walking pace of the user. Some of these speedreduction stages are built into the gearing inside the housings oftransmissions 60. However, the final speed reduction stage is formed bya small diameter drive gear 62 on each end of an axle 64 of eachtransmission 60 that drives a larger diameter driven gear 66 fixedlyattached to one of wheels 8, 10.

Drive gears 62 on the opposite ends of axle 64 of rear transmission 60_(r) engage the backsides of driven gears 66 of rear wheels 10. Thereverse is true for drive gears 62 for front transmission 60 _(f) whichengage the front sides of driven gears 66 of front wheels 8. Thus, whenaxles 64 of transmissions 60 are rotated in opposite directions by theoperation of prime mover 12, front and rear drive wheels 8 and 10 willbe rotated in opposite directions relative to each other. For example,if rear drive wheels 10 are rotated in a forward direction to propelmower 2 forwardly, front drive wheels 8 will be rotated in a rearwarddirection to propel mower 2 in reverse. As a consequence, it should beapparent that only one transmission 60 is active at any given time whilethe other transmission 60 remains inactive. Either transmission 60 canbe selected to be the one that provides forward motion while theremaining transmission 60 will then be the one that provides reversemotion.

Rear transmission 60 preferably has a split axle 64 and provides adifferential action to permit rear wheels 10 to be driven at differentspeeds during a turn, such as when the user swings mower 2 around 180°at the end of a pass when mowing his or her lawn, to avoid tearing orscuffing the grass. Rear wheels 10 may rotate at different speeds duringturns using either an unpowered or powered differential. For example, inan unpowered differential which is preferred due to somewhat lower cost,the portion of split axle 64 powering whichever rear wheel 10 is on theoutside of the turn simply overruns the rotational speed of the portionof split axle 64 powering the rear wheel 10 on the inside of the turn tocreate the difference in wheel speed. Since front wheels 8 of mower 2are typically lifted up off the ground during such a turnaround of mower2, front transmission 60 preferably has a solid axle and lacks anydifferential action, thereby reducing overall cost of mower 2.

Each transmission 60 is provided with a one-way clutch that permits thewheels driven by that transmission 60 to free wheel when mower 2 isbeing propelled in a direction opposite to the direction transmission 60is designed to operate. In the example where one transmission is activeand is driving mower 2 forwardly while the other reverse drivetransmission is inactive and is not in operation, the one way clutch inthe inactive reverse drive transmission permits the drive wheels coupledto that transmission to rotate freely with respect to the internalgearing of the reverse drive transmission to avoid the drag orresistance such internal gearing would otherwise provide when mower 2moves forwardly.

Each front and rear transmission 60 _(f) and 60 _(r) is separatelydriven by its own independent belt drive 68 _(f) and 68 _(r) from driveshaft 14 of prime mover 12. Each transmission 60 is a rockingtransmission of the type disclosed in Stalpes. When handle grip 32 is inneutral and both transmissions 60 are inactive, belts 70 in belt drives68 are sufficiently slack so that the input pulleys on transmissions 60are stationary even though drive shaft 14 of prime mover 12 is rotating.Effectively, mower 2 is at rest even with the engine running when handlegrip 32 is not being pushed or pulled by the user.

However, as the user slides handle grip 32 up or down on handle 26 ineither the downward direction A or the upward direction B, this motionrocks one transmission 60 in a direction (rearwardly about its axle 64for rear transmission 60 _(r) and forwardly about its axle 64 for fronttransmission 60 _(f)) to tighten drive belt 70 to the rockingtransmission while leaving drive belt 70 to other transmission slack. Asdrive belt 70 to the rocking transmission becomes taut, the transmissionbecomes active to begin rotating the pair of wheels powered by therocking transmission. The speed of rotation of axle 64 of the rockingtransmission, and thus the ground speed of mower 2, progressivelyincreases as handle grip 32 is moved ever further in the selecteddirection and the tautness of belt 70 progressively increases. Thus, theground speed of mower 2 progressively increases from zero to a maximumspeed as handle grip 32 travels out of neutral to the end of its rangeof motion in the selected direction A or B. This enables the groundspeed of mower 2 to be matched to the walking pace of the user whethermower 2 is being propelled in forward or reverse.

First and second Bowden cables (not shown) having inner wires carriedwithin outer conduits operably couple handle grip 32 to transmissions60. The first Bowden cable has a “live cable” setup in which a rear endof the outer conduit is fixed or clamped to handle 26 and the front endof the outer conduit is fixed or clamped to a lower end of one handletube 28 or to a rear end of deck 4. The rear end of the inner wire ofthe first Bowden cable is secured to an opening 72 in a pivotal tab 74(see FIG. 2) that is rotated rearwardly when handle grip 32 is moveddownwardly in the direction of arrow A. The front end of the inner wireof the first Bowden cable is then attached to rear transmission 60 _(r)to rock rear transmission 60 _(r) rearwardly during downward motion ofhandle grip 32 in the direction of arrow A. In this “live cable” setupof the first Bowden cable, the downward motion of handle grip 32 causesthe “live” inner wire of the first Bowden cable to slide rearwardlywithin the outer conduit in order to rock rear transmission 60 _(r)rearwardly while the outer conduit remains fixed in place. The “livecable” setup of the first Bowden cable and its interaction with pivotaltab 74 is shown and described in more detail in the Stalpes patent whichhas previously been incorporated by reference herein.

The second Bowden cable has a “live conduit” setup in which the frontend of the inner wire is fixed or clamped in place to deck 4 and therear end of the inner wire is fixed or clamped in place to handle grip32. The rear end of the conduit in the second Bowden cable is fixed orclamped in place to an upper portion of one handle tube 28 adjacent theplace where the rear end of the inner wire of the second Bowden cableattaches to handle grip 32. The front end of the conduit in the secondBowden cable is clamped or fixed to front transmission 60 to rock fronttransmission 60 forwardly during upward motion of handle grip 32 in thedirection of arrow B. In this “live conduit” setup, the upward motion ofhandle grip 32 in the direction of arrow B deforms the shape of theclamped inner wire of the second Bowden cable. This deformation in theshape of the inner wire causes the “live” conduit of the second Bowdencable to slide forwardly over the inner wire to push against fronttransmission 60 _(f) to rock front transmission 60 _(f) forwardly. Onlyone Bowden cable applies force to only one transmission at any giventime with the other Bowden cable not applying force to the othertransmission so that only one transmission at a time is activated.

Mower 2 equipped with traction drive system 38 of this disclosure haspowered operation of rear transmission 60 _(r) to propel mower 2forwardly in a variable speed manner as handle grip 32 is gripped by theuser and the user walks forwardly, thereby sliding handle grip 32downwardly on handle 26 in an amount proportional to the walking pace ofthe user. However, when trying to pull mower 2 back during a trimmingoperation or when trying to mow a small patch of grass in reverse, theuser no longer has to use manual force to manhandle mower 2 in thereverse direction. Instead, the user merely maintains his or her grip oncross bar 36 of handle grip 32 and walks rearwardly at any desired pace.This will slide handle grip 32 upwardly on handle 26 to initiate poweredoperation of front transmission 60 to propel mower 2 rearwardly at avariable ground speed commensurate to the walking pace of the user.Thus, the task of operating mower 2 is greatly eased since mower 2 isself-propelled both in forward and reverse while maintaining thefunctionality of the Personal Pace® control system of The Toro Companythat had previously been used only on mowers that were self-propelled inforward only.

The advantages of a mower that is self-propelled in both forward andreverse is achieved in a cost-effective manner by using mechanical, geardrive transmissions that are both durable and inexpensive in comparisonto using hydraulic motor/pump combinations or electric motor/drivecombinations. Moreover, since transmissions 60 used to drive front andrear wheels 8, 10 are different from one another and are mounted onseparate front and rear axles, this allows rear transmission 60 _(r) tohave a split axle/differential action configuration while fronttransmission 60 _(f) has a solid axle/non-differential actionconfiguration. The manner of driving front and rear wheels 8, 10 usingthe same size drive gears 62 on the ends of the axles of the front andrear transmissions and the same size driven gears 66 on the wheels, butsimply reversing which sides of driven gears 66 are engaged by drivegears 62, leads to increased part commonality and thus reduced cost.This allows a powered, reversible mower to be manufactured and sold at areasonable cost.

Referring now to FIGS. 4 and 5, a second embodiment of a mower accordingto this disclosure is illustrated generally as 2′. The same referencenumerals used in FIGS. 1-3 to refer to components will be used in FIGS.4 and 5 to refer to the same or corresponding components with a primedesignation being used to refer to those components in the secondembodiment, e.g. mower 2′ in FIGS. 4 and 5 as opposed to mower 2 inFIGS. 1-3.

Referring now to FIG. 4, in mower 2′ front transmission 60 _(f)′ and itsaxle 64′ have been relocated from the front to the back of mower 2′ sothat only rear wheels 10′ are reversibly driven by the dualtransmissions 60 _(f)′ and 60 _(r)′ with such transmissions and theiraxles being disposed on opposite sides of the axis of rotation of rearwheels 10′. In this embodiment, front wheels 8′ are present butunpowered with only rear wheels 10′ serving to self-propel mower 2′. Asin the first embodiment concerning mower 2, only one transmission 60′(driven by belt 70′ and having a drive gear 62′ engaged with driven gear66′) is active at any given time while the other transmission 60′(driven by another belt 70′ and also having a drive gear 62′ engagedwith driven gear 66′) remains inactive. Propelling rear wheels 10′ inopposite directions may yield better traction than using front wheels 8′to drive mower 2′ in the direction that is opposite to the directionthat rear wheels 10′ drive mower 2′. This is due to the fact that moreof the weight of a mower like mower 2, 2′ is over rear wheels 10′ ascompared to front wheels 8′. In addition, the filling of a grassclipping collection bag at the rear of mower 2′ with grass clippingsduring a mowing operation only accentuates this rearward weightdistribution.

In mower 2′ as shown in FIG. 4, whichever transmission 60′ is used toproduce forward motion of mower 2′ is preferably one having a splitaxle/differential feature as described earlier with respect to reartransmission 60 _(r) in mower 2. The other transmission 60′ that is usedto produce reverse motion of mower 2′ could also be one having a splitaxle/differential feature since both transmissions are now being used topower rear wheels 10′. However, since the times at which reverse motionis needed and the distances over which mower 2′ would travel in reverseare much more limited than what is required for forward motion,whichever transmission 60′ propels the mower in reverse could remain atransmission having a solid axle without any differential ability.

In addition to the use of both transmissions 60′ to drive rear wheels10′, a simplified Bowden cable coupling setup is used in mower 2′ asshown in FIG. 5. In mower 2′, pivotal tab 74′ now has a second opening76 that is disposed on an opposite side of a horizontal axis ofrotation, illustrated as x in FIG. 5, of a pivot rod 78 compared to thelocation of first opening 72′ in tab 74′. As taught in more detail inStalpes, tab 74′ is rigidly attached to rod 78 to pivot by virtue of thepivoting motion of rod 78 caused by journaling the ends of rod 78 in themower handle tubes 28′ while a middle U-shaped portion 79 of rod 78 iscaptured within a channel 80 in cross member 46′ of slidable handle grip32′. Again, rod 78 and its interaction with cross member 46′ aredetailed more fully in the Stalpes patent which has been incorporated byreference herein.

When the user slides handle grip 32′ downwardly on handle tubes 28′, theportion of tab 74′ having opening 72′ is pivoted rearwardly as describedin connection with the operation of mower 2. This pulls rearwardly onthe “live cable” setup of the first Bowden cable that is connected towhichever transmission 60′ is arranged to drive mower 2′ forwardly toactuate the forward drive transmission 60′. Whichever transmission 60′is arranged to drive mower 2′ in reverse is now connected by a “livecable” setup of the second Bowden cable to the newly added secondopening 76 in tab 74′. Thus, when the user pulls handle grip 32′upwardly on handle tubes 28′ as he or she walks in reverse, the portionof tab 74′ having opening 76 is now pivoted rearwardly to actuate thereverse drive transmission 60′. Since both transmissions 60′ are now atthe rear of mower 2′, the length of the second Bowden cable run isshortened compared to the length required in mower 2, and a “live cable”rather than a “live conduit” setup of the Bowden cable is used. Thissimplifies the routing and arrangement of the Bowden cables. However,the operation of mower 2′ is the same as mower 2, namely pushing handlegrip 32′ downwardly as the user walks forwardly powers mower 2′ in aforward direction at a speed commensurate to the user's walking pacewhile pulling handle grip 32′ upwardly as the user walks rearwardlypowers mower 2′ in a rearward direction at a speed commensurate to theuser's walking pace.

Referring still further to FIG. 5, the use of the double headed tab 74′as described above to activate both transmission 60 _(f)′ and 60 _(r)′in mower 2′ permits a simplified return to natural system 40′. All thatis required now is the use of one or more torsion springs 82, preferablytwo such springs 82, surrounding the ends of rod 78 that lie along anddefine the rotational axis x of rod 78 with such springs being anchoredat one end on rod 78 and at the other end on a portion of the adjacenthandle tube 28′. When handle grip 32′ is located in its centered,neutral, drive disengaging position, torsion springs 82 are in theirunstressed state such that handle grip 32′ is retained in neutral. Asrod 78 is rotated about axis x in either one direction or the other dueto motion of handle grip 32′ relative to handle tubes 28′, torsionsprings 82 get coiled up or twisted in one direction or the other toresist the motion of handle grip 32′ out of neutral. When the usersubsequently releases handle grip 32′, the biasing force built up in thecoiled torsion springs 82 is now free to act on handle grip 32′ to moveit back to neutral.

The return to neutral system 40′ as shown in FIG. 5 is simpler and thusless costly than system 40 shown in FIGS. 1-3 and takes up less space onmower 2′. Thus, the cable coupling setup and return to neutral system40′ shown in FIG. 5 could be used with mower 2 shown in FIGS. 1-3 if sodesired.

FIGS. 6A-10 illustrate a walk power mower 200 in accordance with anotherembodiment of the present disclosure. With the exceptions noted below,the mower 200 may be mostly identical to the mower 2 (or 2′) alreadydescribed herein. For example, the mower 200 may include a cutting deck204 that may be self-propelled, i.e., it may include a variable speedtraction drive system having one or more transmission(s) carried by thedeck as described herein. The drive system may be capable of selectivelyproviding driving power to one or more of the wheels in both a forwardand a reverse direction. Alternatively, the mower 200 may incorporate aconventional transmission (e.g., rear-wheel drive, front-wheel drive, orall-wheel drive) that is capable of selectively providing driving powerto one or more of the wheels in only a single (e.g., forward) direction.In yet other embodiments, the mower may lack a transmission (i.e., itmay be push-powered only). For brevity, aspects of the mower 200 thatare either commonly known in the art, or that are already describedherein above, are not further described below.

As shown in FIGS. 6A-6B, the grass cutting deck 204 is supported uponthe ground 203 by a pair of ground-engaging front wheels 208 and a pairof ground-engaging rear wheels 210. Again, the traction drive system maydrive at least one of the front wheels and/or rear wheels forwardly topropel the mower 200 as it traverses the ground 203 in a forwarddirection, while the same or different wheel(s) may optionally be drivenrearwardly to propel the mower in the reverse direction as alreadydiscussed herein. In other embodiments, the wheels of the mower may beundriven, i.e., the mower may move under operator push-power only.

The deck 204 may further support a prime mover 212 such as an electricmotor or gasoline-powered engine. The prime mover may power not only thedrive wheels of the mower, but also a cutting blade 16 (see FIG. 3)operable to rotate within the deck.

A handle 226 extends upwardly and rearwardly from the deck 204 as shownin FIGS. 6A-6B. As with the handle 26 of the mower 2, the handle 226 mayinclude a pair of laterally spaced-apart and parallel handle members ortubes 228 extending upwardly and rearwardly from the cutting deck. Eachhandle tube includes an upper end forming a grip area, e.g., crossmember 230 and/or handle grip 232. Lower ends of each handle tube 228may be pivotally attached to the deck 204, e.g., to a rear portion ofthe deck. While shown as incorporating two parallel handle tubes, mowerswith handles formed from a single handle member or tube are alsocontemplated.

The handle 226 of the exemplary mower 200 may include a U-shaped handlegrip 232 having a pair of laterally spaced legs 234 connected by anupper cross bar 236 at or near the upper ends of the handle members. Aswith the mower 2, legs 234 of the handle grip 232 may be telescopicallyattached near the upper ends of the handle tubes 228 for slidingmovement relative thereto. Thus, handle grip 232, like the grip 32described above, forms a control system or member slidable downwardly(and optionally upwardly) on the handle tubes 228 as the user walksforwardly (and optionally, rearwardly) while gripping the cross bar 236with the user's hands. That is to say, the control member of the handle226 is operable to engage the variable speed traction drive system toselectively propel the cutting deck 204 in one or both of the forwardand reverse directions in a manner already described herein with respectto the mowers 2 and 2′.

Of course, in other embodiments, the handle 226 may include analternative control member for interfacing with the traction drivesystem to control mower propulsion, or it may completely lack any suchcontrol member/traction drive system (i.e., when configured as apush-powered mower).

The lower ends of the handle tubes 228 may pivotally attach to the deck204 such that the handle 226/handle tubes 228 may pivot about ahorizontal transverse pivot axis 250 (e.g., an axis that is transverseto a direction of forward or reverse travel of the deck) as shown inFIG. 7. To accommodate this pivotal connection, the mower 200 mayinclude left and right upright float plates 252 associated with the leftand right handle tubes 228, respectively. The plates 252 may each definean aperture operable to receive a fastener (e.g., pin/nut 254) passingthrough an aligned aperture in its associated handle tube 228. Thepins/nuts 254 thus define the pivot axis 250 about which the handle(e.g., handle tubes) may pivot.

Each handle tube 228 may also include a handle latch 256. Each latch mayinclude a lever 258 that is rotatable (e.g., 90 degrees) to allowextension and retraction of a latch pin 260. In the operating positionillustrated in FIG. 7, each pin 260 may be engaged with a slot 264formed in the associated plate 252. The slots constrain the handle 226(handle members 228) not to a singular position like the notches 262(described below), but rather allow the handle 226/tubes 228 to pivot,relative to the deck 204, between: an upper stop 266 a (upper end of theslot 264) corresponding to the handle being in a first operatingorientation R (see FIG. 10); and a lower stop 266 b (lower end of theslot) corresponding to the handle being in a second operatingorientation B (see also FIG. 10). The upper and lower stops 266 a, 266 bthus define an operating range of pivotal motion of the handle (i.e., ofthe handle tubes). In one embodiment, the operating range of pivotalmotion is at least about 5 degrees (i.e., about 5 degrees or more) ofrotation about the pivot axis 250. For example, in some embodiments, arange of about 5-20 degrees, or a range of about 8-12 degrees, iscontemplated.

By retracting the latch pins 260, the handle 226/handle members 228 mayalso be moved from the operating orientations to a third or storageorientation S shown in broken lines in FIG. 10. In the storageorientation S, the handle 226/handle tubes 228 is positioned generallyvertically to reduce the footprint of the mower during non-use. Thehandle 226 may be latched in the storage orientation by extending thepins 260 into engagement with associated notches or openings 262 formedon the plates 252 (see FIG. 7). As one can appreciate, the storageorientation S is outside of the operating range of pivotal motiondefined by the slots 264 and stops 266 a, 266 b. While shown as placingthe handle 226/handle members 228 in a generally vertical storageposition, such a configuration is not limiting. For instance, otherembodiments may locate the notches 262 (or, alternatively, provide anadditional set of notches 262) to allow for handle 226/handle member 228storage at a different angular orientation. One such orientation mayplace notches 262 such that the handle 226/handle members 228 extendforwardly and generally parallel to the ground 203 (see FIG. 10) when ina storage orientation S′.

As shown in the exploded view of FIG. 8, each plate 252 may rotatablyattached to an upright flange 253 of the mower deck via its associatedpin/nut 254 such that it may rotate about the transverse pivot axis 250.To rotationally secure each plate 252 in place relative to itsassociated flange 253, a fastener 255 and threaded knob 257 may beprovided. The fastener 255 may be inserted through an aperture 259 inthe flange 253 and into one of two (or more) holes 261 a, 261 b formedin the bracket 252. By pivoting the plate until the appropriate hole 261a, 261 b aligns with the aperture 259, the mower may provide varyinghandle operating heights to accommodate a broad range of users. Once thefastener 255 is inserted through the desired hole 261 a or 261 b of eachplate 252, the threaded knob 257 may be secured to the fastener 255 tolock the plate 252 in place.

With reference now to FIGS. 7-10, the mower 200 may also include ahandle float system adapted to bias the handle (e.g., the handlemembers) toward the upper stop 266 a. In one embodiment, the floatsystem includes a resilient member, e.g., left and right resilientmembers 272, operatively positioned between each lower stop 266 b of thecutting deck and its respective handle member 228. For example, in theillustrated embodiment, the left and right resilient members 272 may bepositioned such that they abut a lower side of the left and right handletubes 228, respectively, when the handle is at rest (when the handle isin the operating orientation R (see FIG. 10) and no user loads areapplied to the handle). In some embodiments, the resilient members 272may bias the tubes 228 against their respective upper stops 266 a.However, in other embodiments, the resilient members may be configuredto bias the handle members to a location that is at or near (e.g.,slightly short of) the upper stops when the handle is at rest.

The term “resilient member,” as used herein, includes most any devicethat is able to deform, displace (e.g., displace a contained fluid),distort, or contract under load, and then spontaneously return to (ornear) its original configuration when the load is removed. Thus, inaddition to the neoprene cylinder configuration described below, otherresilient members, e.g., a pneumatic spring, a mechanical or fluidicshock absorber, etc., are also contemplated within the scope of thisdisclosure.

To secure each resilient member 272 in place, the mower deck 204, e.g.,the plates 252, may each define a seat 274. In the illustratedembodiment, each seat is formed by a bent tab of its associated plate252 (see FIG. 8). The seat 274 may define an aperture adapted to receivean integral threaded stud 276 of the member 272 as shown in FIGS. 8 and9. The stud 276 may pass through the aperture in the seat 274 and besecured relative to the plate 252 with a nut 278.

Each resilient member 272 may be constructed of a resilient elastomericmaterial. For example, while not wishing to be bound to any specificconfiguration, each member 272 may be a neoprene disk or cylinder havinga durometer of 60 Shore A. In the illustrated embodiment (see, e.g.,FIG. 9), the cylinder may have a height of about one inch and a diameterof about 1.25 inches. However, members of other materials, hardness,size, and geometry are certainly contemplated.

During operation of the mower 200 over the ground 203, the handle 226may be used to control forward propulsion at already described abovewith reference to the mower 2. For example, as shown in FIG. 10, theuser may apply a force 280 that either: displaces the handle grip 232downwardly along the handle tubes 228 to engage the traction drivesystem; or, where the mower is push-powered, pushes against the crossmember 230 sufficiently to move the mower forwardly. In the case of theformer, as the user walks forwardly and applies this input force 280 tothe handle grip 232, the handle grip moves from a neutral position(wherein the traction drive system is inactive), to a first engagedposition, causing one of the transmissions to engage and propel themower in the forward direction.

As this user-applied force 280 is offset from the deck 204, it may alsoproduce a pivoting force on the handle 226/handle tubes 228 (about theaxis 250 (see also FIG. 7)) in a clockwise direction 282 as shown inFIG. 10. However, the upper stop 266 a of the slot 264 (see also FIG. 7)will effectively limit this pivotal movement of the handle (relative tothe deck 204). As stated above, however, some minimal pivotal movementin the direction 282 may be accommodated before contact occurs betweenthe pin 260 and the upper stop 266 a. However, once the hard stop 266 ais contacted, further movement of the handle 226 (relative to the deck)in the direction 282 may be constrained.

When the user instead applies a pulling input force 284 to the mowerhandle 226 (e.g., directly to the handle grip 232) in a reversedirection, the handle grip 232 may move upwardly along the handlemembers from the neutral position to a second engaged position. In thesecond engaged position, the traction drive system may activate forpropulsion in the reverse direction. Moreover, as this pulling forceoccurs, the handle 226/handle members 228 may pivot (about the pivotaxis 250) in a counterclockwise direction 286, i.e., toward the lowerstop 266 b (see FIG. 7) corresponding to the second operatingorientation B of the handle. As this pivotal movement occurs, eachhandle tube 228 may compress and resiliently deform its associatedmember 272. As a result, the moment of the handle 226 is reacted, atleast initially, by compression of the members 272, allowing substantialdownward movement of the handle (e.g., cross member 230/hand grip 232)to occur and be isolated (at least initially) from corresponding upwardmovement of the mower's front wheels 208. Of course, once the pins 260bottom out on the hard stop 266 b (see FIG. 7), further movement of thehandle 226 in the direction 286 may begin to elevate the mower's frontwheels 208.

With a mower 200 like that described herein incorporating two neoprenemembers 272 as described above, the handle 226 may pivot about its pivotaxis 250 (in the direction 286) about 10 degrees from its at restposition R (shown in solid lines in FIG. 10) to a bottom position Bbefore the front wheels 208 would begin to rise. While varyinggeometries are possible, one embodiment of the mower 200 may use ahandle that is roughly 32 inches long (measured from a centerline of thecross member 230 to the pivot axis 250). With this construction, thecross bar 230 may move a linear distance (e.g., along an arc 288) ofapproximately 5-10 inches, e.g., 6 inches, as the handle tubes move fromthe upper stop 266 a to the lower stop 266 b (see FIG. 7). Of course,depending on the stiffness/configuration of the members, the weight andweight distribution of the mower, and the magnitude of the force 284,the members may effectively form the lower stops. That is to say, themembers 272 may reach a maximum deflection before the pins 260 contactthe lower stops 266 b. However, in other embodiments, the members maycontinue to compress up and until the lower stops 266 b are contacted bytheir respective pins 260.

Floating handles such as those described herein may thus allow at leastsome degree of downward movement of the handle to occur without causingassociated lifting of the front wheels. As a result, mowers that utilizea sliding control member to initiate rearward propulsion (e.g., like thehandle 226 described herein) may permit rearward/downward handlemovement without causing front wheel lifting (at least during typicaland expected operation). This advantage may be especially useful formowers that incorporate reverse drive at the front wheel axle. However,even for mowers that provide no powered reverse operation, floatinghandles in accordance with embodiments of the present disclosure maystill assist in keeping the front wheels in contact with the groundduring reverse pulling of the mower.

While described herein in the context of a four-wheel mower, such aconfiguration is exemplary only. For instance, it is contemplated thatembodiments of the present disclosure may find application to mowershaving tri-wheel configurations (e.g., having only a single front wheeland/or a single rear wheel), as well as to most any othermulti-wheel/multi-axle configuration. Yet further, mowers usingground-engaging members other than wheels (e.g., a rear roller) are alsopossible. Still further, embodiments of the present disclosure may findapplication to mowers entirely lacking physical ground-engaging members.For example, hover mowers, which float above the ground on a cushion ofair generated by the mower, may benefit from the concepts (e.g., thebiased handle) described herein. Those of skill in the art will furtherrealize that embodiments of the present disclosure may also findapplication to walk-behind power equipment other than lawn mowers havinga ground-traversing tool housing other than a cutting deck including,for example, aerators, wheeled debris blowers, cultivators, and thelike.

Various modifications will be apparent to those skilled in the art.Thus, the scope of this invention is not to be limited to the details ofthe various embodiments described herein, but shall be limited only bythe appended claims, and equivalents thereof.

The invention claimed is:
 1. A walk power mower comprising: a grasscutting deck surrounding a grass cutting member, wherein the cuttingdeck is adapted to travel over the ground in both a forward directionand a reverse direction; a handle comprising an upwardly and rearwardlyextending handle member, wherein the handle member includes: an upperend comprising a grip area; and a lower end pivotally attached to thecutting deck such that the handle member pivots about a transverse pivotaxis within an operating range of pivotal motion defined by: an upperstop corresponding to the handle being in a first operating orientation;and a lower stop corresponding to the handle being in a second operatingorientation, the operating range of pivotal motion being at least about5 degrees; and a resilient member operatively positioned between thelower stop and the handle member, wherein the resilient member isadapted to bias the handle member to a location at or near the upperstop.
 2. The mower of claim 1, wherein the resilient member comprises aneoprene cylinder.
 3. The mower of claim 1, wherein the cutting deckcomprises a vertical float plate defining the transverse pivot axis. 4.The mower of claim 3, wherein the float plate is rotatable relative tothe cutting deck about the transverse pivot axis.
 5. The mower of claim3, wherein the resilient member is attached to the float plate.
 6. Themower of claim 3, wherein the float plate defines a slot adapted toreceive therein a pin associated with the handle member, wherein ends ofthe slot define the upper and lower stops.
 7. The mower of claim 6,wherein the pin is adapted to withdraw from the slot such that thehandle member can pivot about the transverse pivot axis to a thirdstorage orientation that is outside of the operating range of pivotalmotion.
 8. The mower of claim 1, wherein the operating range of pivotalmotion is about 8-12 degrees.
 9. The mower of claim 1, wherein the griparea moves a linear distance of about 5-10 inches as the handle membermoves between the upper stop and the lower stop.
 10. A walk power mowercomprising: a grass cutting deck supported upon the ground by a frontwheel and a rear wheel, the cutting deck surrounding a grass cuttingmember, wherein the cutting deck is adapted to traverse the ground inboth a forward direction and a reverse direction; at least onetransmission adapted to selectively provide driving power to at leastone wheel of the front and rear wheels; a handle comprising first andsecond laterally spaced-apart and parallel handle members each extendingupwardly and rearwardly from the cutting deck, wherein the first andsecond handle members each comprise: an upper end; and a lower endpivotally attached to the cutting deck such that the handle memberspivot about a transverse pivot axis within an operating range of pivotalmotion defined by: an upper stop corresponding to the handle being in afirst operating orientation; and a lower stop corresponding to thehandle being in a second operating orientation, the operating range ofpivotal motion being about 5-20 degrees; a control member carried at ornear the upper ends of the first and second handle members, wherein thecontrol member, when moved to a first engaged position, is adapted toplace the transmission into operation so that the transmission propelsthe mower in the forward direction; and first and second resilientmembers positioned between the deck and the first and second handlemembers, respectively, the first and second resilient members adapted tobias the first and second handle members to a location at or near theupper stop.
 11. The mower of claim 10, wherein the first and secondresilient members resiliently deform when the handle is pivoted towardthe second operating orientation.
 12. The mower of claim 10, wherein thefirst and second resilient members isolate downward movement of thehandle from upward movement of the front wheel.
 13. The mower of claim10, further including a second transmission adapted to provide drivingpower to at least one wheel of the front and rear wheels.
 14. The mowerof claim 13, wherein movement of the control member to a second engagedposition places the second transmission into operation so that thesecond transmission propels the mower in the reverse direction.
 15. Awalk power mower comprising: a grass cutting deck supported upon theground by a pair of front wheels and a pair of rear wheels, the cuttingdeck surrounding at least one grass cutting blade; a variable speedtraction drive system carried on the cutting deck and adapted toselectively provide driving power to at least one wheel of the front andrear pairs of wheels to propel the mower over the ground in both aforward direction and a reverse direction; a handle comprising first andsecond laterally spaced-apart and parallel handle members extendingupwardly and rearwardly from the cutting deck, wherein the first andsecond handle members each comprise: an upper end; and a lower endpivotally attached to a rear portion of the cutting deck such that thehandle members pivot about a transverse pivot axis within an operatingrange of pivotal motion defined by an upper stop and a lower stop; acontrol system carried at or near the upper ends of the first and secondhandle members, the control system operable to engage the traction drivesystem to selectively propel the cutting deck in both the forwarddirection and the reverse direction; and first and second resilientmembers positioned between the deck and the first and second handlemembers, respectively, the first and second resilient members adapted toresiliently deform when the handle members pivot, about the transversepivot axis, from a position at or near the upper stop toward a positionat or near the lower stop.
 16. The mower of claim 15, wherein thevariable speed traction drive system comprises a first transmissionoperable to propel the mower in the forward direction, and a secondtransmission operable to propel the mower in the reverse direction. 17.The mower of claim 15, wherein each resilient member is secured relativeto the deck such that its associated handle member abuts the resilientmember when the handle is at rest.
 18. The mower of claim 15, whereinthe operating range of pivotal motion is about 5-20 degrees.
 19. Themower of claim 18, wherein the operating range of pivotal motion isabout 8-12 degrees.
 20. A walk power mower comprising: a grass cuttingdeck supported upon the ground by a pair of front wheels and a pair ofrear wheels, the cutting deck surrounding at least one grass cuttingblade; a variable speed traction drive system carried on the cuttingdeck and adapted to selectively provide driving power to one or morewheels of the front and rear pairs of wheels to propel the mower overthe ground in both a forward direction and a reverse direction; a handlecomprising first and second laterally spaced-apart and parallel handlemembers extending upwardly and rearwardly from the cutting deck, whereinthe first and second handle members each comprise: an upper end; and alower end pivotally attached to a rear portion of the cutting deck suchthat the handle members pivot about a transverse pivot axis within anoperating range of pivotal motion defined by an upper stop and a lowerstop; a slidable handle grip attached to the upper ends of the first andsecond handle members, the slidable handle grip having a neutralposition on the handle corresponding to the traction drive system beinginactive, wherein the slidable handle grip is: selectively slidable outof the neutral position and downwardly along the handle members, when auser walks forwardly and pushes against the handle grip, to engage thetraction drive system for propulsion of the mower in the forwarddirection; and selectively slidable out of the neutral position andupwardly along the handle members, when the user walks rearwardly andpulls against the handle grip, to engage the traction drive system forpropulsion in the reverse direction; and first and second resilientmembers positioned between the deck and the first and second handlemembers, respectively, the first and second resilient members adapted toresiliently compress during downward movement of the handle toward thelower stop, thereby isolating such downward movement of the handle fromupward movement of the pair of front wheels.